Side guard for conveyers



-'3, 1942- A. o. HURXTHAL ETAL 2,304,692

smi; GUARDS, FQR couvn'mns Filed April 4, 1939 2' Sheets-Sheebl Dec. 8, 1942- A o. HURXTHAL EI'ALI 2,304,692

, SIDE GUARDS FOR CONVEYERS Filed April 4, 1939 2 Sheets-Sh e et 2 Patented Dec. 8, 1942 'uNrrso SIDE GUARD FOR CONVEYERS Alpheus 0. Hurxthal, Wyncote, and Stanislaus Pa., assignors to Proctor Bogaty, Philadelphia, & Schwartz, Incorporated,

Philadelphia, Pa., a

'7 Claims.

rial and the perforations of the conveyer surface on which the material is resting.

In some of the early installations of apparatus of the kind noted above, the longitudinal side edges of the conveyer traveled under and relative to the lower edges of vertically disposed stationary side guards which were provided primarily to direct the passage of the air to and through the material on the carrying portion of the conveyer; and to retain the material on the conveyer. working clearance provided between the top surface of the conveyer and the lower edges of the stationary side guards permitted the escape of the drying or processing medium and the loss of some of the material carried along by such escaping air etc., a representative structure being illustrated, for example, in Fig. 3 of the common assignees prior Patent No. 1,492,418, dated April 29, 1934.

In order to prevent such loss of material, and in order to make it possible to load the conveyers to a uniform depth from edge to edge thereof, the opposite longitudinal side edges of subsequent conveyers were provided with traveling side guards, i. e. guards standing in substantially vertical planes upwardly from and fixed to the side edges of the conveyer, for concurrent movement therewith, as clearly disclosed in the common assignees prior Patent No. 1,634,963, dated July 5, 1927. This improvement resulted in a more uniform drying of the material in transit and increased the capacity of the apparatus.

The traveling side guard feature of the last mentioned patent was later combined in practice with the stationary side guard feature disclosed in the first mentioned patent. Here again it was necessary to provide a working clearance between the traveling side guardsand the stationary side guards, with overlapping edge portions of said guards arranged in vertical planes, in laterally spaced relation to each other, usually with the lower marginal portion of the stationary guard disposed inwardly of the conveyer with re- However, the necessarytraveling side guards. Here again the requisite working clearance permitted the escape of drying or processing medium and the loss of material.

With the advent of the fine mesh screen sections and the improved hinge joint between such sections, as disclosed in the common assignees prior Patent No. 2,007,862, dated July 9, 1935, this type of apparatus came into general use for the drying or processing of fine granular materials, and therewith came the problem of preventing loss of processing medium and the finer dust-like portions of the material suspended in the medium escaping through the working clearance between the stationary and traveling guards.

The seemingly obvious solution to the problem was to reduce the clearance to an absolute minimum or to effect actual contact therebetween. Normally, the side guards, both the stationary and the traveling guards, are necessarily composed of rather heavy gage sheet metal, to withstand any hard usage to which they may be subjected. Furthermore, it is practically impossible to eliminate all lateral movement of the conveyer as it travels along its supports. This combination of conditions resulted in a heavy pressure being produced between the traveling and the stationary side guards at one side or the other or alternately, but still causing an opening to exist at the opposite side of the conveyer between the non-contacting side guards through which the air and the material might escape. Such heavy pressure caused rapid deterioration of the heavy gage guards and, furthermore, resulted in fine particles of metal becoming mixed with and contaminating the material on the conveyer, which proved to be more objectionable than the loss of air and material through the working clearance.

The object of the present invention is to eliminate the above noted objectionable characteristics found in apparatus employing movable and stationary side guards. It has been found that these objections may be overcome by providing a resilient contact between the movable and stationary guards; and toward this end it has been found that such an arrangement is made possible by constructing either the movable side guards or the stationary side guards of relatively light gage resilient material, such as sheet steel, having sufiicient flexibility to maintain a sliding sealing contact between the two during longitudinal movement of the conveyer with respect to the upper marginal portions of the spect to the stationary side guards, and during lateral swaying or other sidewise movement of the conveyer during such longitudinal travel thereof.

Light gage guards, however, are not entirely satisfactory in that they are subject to damage during use. The practical solution tothe problem has resolved into the provision of side guards of substantially heavy gage resilient sheet metal with auxiliary means for flexing either the traveling or the stationary guards laterally into contact one with the other, and maintaining this resilient contact throughout the travel of the conveyer and the guards thereon with respect to the stationary guards, the more practical construction being to make the traveling guards of a rigid material and providing the resiliency in the stationary guard, with the auxiliary flexing means cooperating with the stationary guard to maintain sliding sealing contact thereof with the movable guard.

In the accompanying drawings:

Fig. 1 illustrates one application of the principles of the present invention, wherein the lower edges of the stationary guards are disposed inside and in resilient contact with the inner surfaces of the movable side guards;

Fig. 2 discloses a similar application of the principles of the invention with the lower edges of the stationary guards disposed outside and in sealing contact with the outer surfaces of the traveling guards;

Fig. 3 discloses a modification wherein the stationary guard lies at right angles to and makes resilient sealing contact with the upper edge of the traveling guard; and

Fig. 4 illustrates another modification of the invention,

As shown in Figs. 1 and 2 of the drawings, in each instance, the conveyer is illustrated in broken lines and indicated generally at I, said conveyer comprising the usual side chains and roller supports indicated at 2, 2, with the supporting rollers 3 riding on supporting tracks 4, rigidly mounted on the side walls or structural elements 5, 5 of the drying chamber or processing compartment through which the conveyer I travels. The body of the conveyer is illustrated at 6, and, as noted, is preferably of the foraminous type composed of wire mesh screen attached along its opposite edges to the side chains I, 1, between horizontally extending flanges 8, 8 of said side chains, by securing means 9, such as rivets, bolts, etc. Such construction is shown as a matter of illustration, as it will be understood that the construction of the conveyer is not limited to that shown in the drawing and may take any desired form.

As shown in Figs. 1 and 2, each of the opposite longitudinal edges of the conveyer I is provided with a substantially vertical upwardly extending side guard I0, which may be of a sectional construction having the ends of the sections disposed in overlapping relation to each other at the pintles of the side chains of the conveyer and the coinciding pivotal connections between the sections of the body portion 6 of the conveyer, as clearly illustrated in the common assigneees prior patents, No. 1,634,963 aforesaid, and No. 2,019,389, dated October 29, 1935.

In the present instance the side guards III are illustrated as having base flanges II, I I mounted on the upper lateral flanges or lips 8 of the side chains I, and secured thereto by any suitable fastening means I2, which may also constitute.

the means by which the body 6 of the conveyer is secured at its opposite edges to the side chains 1, I thereof.

As shown in Fig. 1, the upper edge portion I3 of the guard II) at one side of the conveyer is arranged in overlapping contacting relation to the lower edge portion I4 of a stationary guard I5, the extent of overlapping between the moving and stationary guards being indicated at I6. The upper portion ll of the stationary side guard I5 is secured, as by bolts I8 for example, to the side wall or to rigid structural elements 5 of the dryer proper.

The stationary side guard I5 is composed of resilient sheet material, such as sheet steel, and the width, vertically, of the portion I9 intermediate the edges I4 and I 1 is suflicient to permit lateral flexing of the lower edge I4, to maintain the sliding sealing contact I6 at all times during longitudinal movement of the conveyer, and during any incidental side movement of the conveyer. The side guard I5 is so constructed and secured in position that a resilient pressure in the direction of the arrow 12 is maintained at all times, which results in maintenance of the overlapping contact I6 between the upper edge I3 of the movable guard I I] and the lower edge I4 of the stationary guard I5 during said movement of the conveyer.

At the opposite side of the conveyer I, a stationary side guard 25 is provided, with the lower edge portion 24 thereof in overlapping relation to the upper edge portion 23 of the movable side guard III at said side of the conveyer I, providing a sliding sealing contact area 25 between the two. The upper end 27 of the guard 25 is secured, as at 28, to a fixed portion 5 of the dryer or other chamber or compartment. In this instance, as in the previous instance, the portion 29 of the guard 25 is of suflicient length and resiliency to efiect constant pressure in the direction of the arrow b. In this instance, however, an auxiliary means in the form of an open bowspring 20 is provided, with one of its ends secured at 2I to the lower portion of the guard 25, adjacent the upper edge 23 of the movable guard III, and the second end of the bow-spring 20 secured, at 22, to the rigid stationary structure 5.

The two legs of the bow-spring 20 tend to move toward each other in the directions of the arrows 0, 0 respectively, and thus accentuate the pressure movement of the guard 25 in the direction of the arrow b.

In Fig. 2, stationary guards 35, 35 are provided at the opposite sides respectively of the conveyer, with the lower edge portions 34, 34 thereof in overlappin relation with the upper edge portions 33, 33 of the movable side guards III, III. The upper edge portions 31, 31 of the guards 35, 35 are permanently secured to rigid stationary portions 5 of the structure of the dryer etc. through which the conveyer is moving.

In this instance the main body portions 39, 39 of the guards 35, 35 respectively, are of a resilient character and of suflicient length to provide and exert pressure in the direction of the arrows d, d, to create a sliding sealing contact between the edge portions 33 and 34 of the guards I0 and 35 respectively.

Theexertion of the pressure in the direction of the arrow d, d is accentuated, in the present instance, by flat springs 30, 30, each having one end secured at 3I to the guard 35 with which it is associated, and the second end 32 of each spring bearing against the rigid structure 5.

In the instance of Fig. 2, a wear or sealing strip 'contact with a wear 'zontally extending edge portion Mi of a resilient stationary guard 45, which latter is secured adjacent its upper edge 41 to the rigid stationary "34 of 'the guards l9 and 35 respectively. These wearing strips, in this instance, are formed of a baked brake lining or the equivalent and form a wear resisting seal 36 between the relatively movable guards Hi and 35. Obviously, these strips 40 may be secured to either one or the other of the side guards and, in the present instance, such strips are secured to the lower edge portions 34 of the stationary guards 35, as by rivets or bolts 4|, 4!, having counter-sunk heads 42, 42 buried in the strips 40, Ml below the surface thereof which bears against the movable guard I0.

In Fig- 3 the upper edge of the traveling side= guard ma is provided with a lateral flange 43 for strip 40 secured to a hori- If desired, auxiliary springs 50 having one leg or end 52 secured to the rigid stationary structure and the opposite end 5| secured to or making contact with the edge portion 44 of the stationary guard augment resilient movement of the horizontal portion of the stationary guard 45 toward the upper edge portion 43 of the traveling guard Ida in the direction of the arrow e to effect a sliding sealing contact 46 therebetween.

In Fig. 4 a longitudinally corrugated or equivalently resilient stationary guard 55 is provided, with a horizontal lip or flange 54 underlying a laterally extending flange 53 on the traveling guard Iilb, with the upper edge portion 5? secured to the rigid stationary structure 5 and exerting an upward resilient pressure, in the direction of the arrow 1, to form a sliding sealing contact 56 between the stationary guard and the traveling guard.

With any of the structures described above a yielding constant sealing contact is provided between the movable guards and the stationary guards, which eliminates the working clearance heretofore required by the rigid construction previously employed. Thus, loss of drying or processing medium and material from the conveyer is eliminated and undesirable Wearing away of the side guards and a resultant contamination of the material carried by the conveyor, is avoided.

We claim:

1. In a structure of the kind described, comstructure 5.

prising a stationary framework, a foraminous endless belt conveyer supported for horizontal longitudinal movement relative to said framework, and upwardly extending side guards secured to said conveyer along the opposite marginal edges respectively thereof for concurrent movement therewith to prevent lateral displacement of material therefrom, wherein said material is subjected to the influences of air circulating substantially perpendicular to the carrying I plane of the conveyer, the combination therewith of inherently resilient stationary guards extending uninterruptedly along the path of movement of the conveyer adjacent said marginal edges respectively thereof, and means for securing one edge of each stationary guard to said framework with the opposite edge free and resiliently pressing against one of said traveling side guards in overlapping relation to the upper marginal edge of said traveling side guard, to prevent escape of air and entrained particles of said material 45, may be provided to;

between said overlapping edges of said station'- framework, and. upwardly extending side guards secured to said conveyer along the opposite mar-- ginal edges respectively thereof for concurrent movement therewith to prevent lateral displacement of material therefrom, wherein said material is subjected to the influences of air circu lating substantially perpendicular to the carry' ing planeof the conveyer, the combination therewith of inherently resilient stationary guards extending uninterruptedly along the path of movement of the conveyer adjacent said marginal edges respectively thereof with said stationary guards extending upwardly and outwardly from said marginal edges of the conveyer over said side chains, and means for securing one upper edge of each stationary guard to said framework with the opposite edge free end resiliently pressing against one of said traveling side guards in overlapping relation to the upper marginal edge of said traveling side guard, to prevent escape of air and entrained particles of said material between said overlapping edges of said stationary guard and traveling guard and the deposit of said particles on said side chains.

3. In a structure of the kind described, comprising a stationary framework, a foraminous endless belt conveyer supported for horizontal longitudinal movement relative to said framework, and upwardly extending side guards secured to said conveyer along the opposite marginal edges respectively thereof for concurrent movement therewith to prevent lateral displacement of material therefrom, wherein said material is subjected to the influences of air circulating substantially perpendicular to the carrying plane of the conveyer, the combination therewith of inherently resilient stationary guards extending uninterruptedly along the path of movement of the conveyer adjacent said marginal edges respectively thereof, means for securing one edge of each stationary guard to said framework at an elevation spaced above the upper edges of said traveling guards with the opposite edge free and resiliently pressing against one of said traveling side guards in overlapping relation to the upper marginal edge of said traveling side guard, to prevent escape of air and entrained particles of said material between said overlapping edges of said stationary guard and traveling guards, and an auxiliary pressure spring having one end engaging one of said stationary guards at a point intermediate the fast and free edges thereof and the opposite end engaging said framework at a, point spaced from said guardsecuring means.

4. In a structure of the kind described, comprising a stationary framework, a foraminous endless belt conveyer supported for horizontal longitudinal movement relative to said framework, and upwardly extending side guards secured to said conveyer along the opposite marginal edges respectively thereof for concurrent movement therewith to prevent lateral displacement of material therefrom, wherein said material is subjected to the influences of air circulating substantially perpendicular to the carrying plane of the conveyer, the combination therewith of inherently resilient stationary guards extending uninterruptedly along the path of movement of the conveyer adjacent said marginal edges respectively thereof, means for securing one edge of each stationary guard to said framework with the opposite edge free and resiliently pressing against one of said traveling side guards in overlapping relation to the upper marginal edge of said traveling side guard, to prevent escape of air and entrained particles of said material between said overlapping edges of said stationary guard and traveling guard, and an auxiliary pressure spring having one end secured to one of said stationary guards adjacent said free edge thereof and its opposite end engaging said framework at a point spaced from said guard-securing means.

5. In a structure of the kind described, comprising a stationary framework, a foraminous endless belt conveyer supported for horizontal longitudinal movement relative to said framework, and upwardly extending side guards secured to said conveyer along the opposite marginal edges respectively thereof for concurrent movement therewith to prevent lateral displacement of material therefrom, wherein said material is subjected to the influences of air circulating substantially perpendicular to the carrying plane of the conveyer, the combination therewith of inherently resilient stationary guards extending uninterruptedly along the path of movement of the conveyer adjacent said marginal edges respectively thereof, means for securing one edge of each stationary guard to said framework with the opposite edge free and resiliently pressing against one of said travelingside guards in overlapping relation to the upper marginal edge of said traveling side guard, to prevent escape of air and entrained particles of said material between said overlapping edges of said stationary guard and traveling guard, and an auxiliary pressure spring having one end secured to one of said stationary guards adjacent said free edge thereof and its opposite end secured to said framework in spaced relation to said guard-securing means.

6. In a structure of the kind described, a framework, a foraminous endless conveyer, means for. supporting said conveyer on said framework for longitudinal movement relative to said framework, upwardly extending side guards secured to said conveyer along the opposite marginal edges thereof, guards mounted on and coextensive with said framework, and means resiliently pressing said guards on the framework against said guards secured to the conveyer.

'7. In a structure of the kind described, a framework, a foraminous endless conveyer, means for supporting said conveyer on said framework for longitudinal movement relative to said framework, upwardly extending side guards secured to said conveyer along the opposite marginal edges thereof, guards mounted on and coextensive with said framework, and spring means resiliently pressing said guards on the framework against said guards secured to the conveyer.

ALPI-IEUS O. HURXTHAL. STANISLAUS BOGATY. 

